Many CVDisplayLink threads created and destroyed while watching a You…

…Tube video

https://bugs.webkit.org/show_bug.cgi?id=181396

Reviewed by Simon Fraser.

When watching some YouTube videos (or any video with default controls), event handlers for
the "timeupdate" event which use rAF will cause the underlying platform objects to be
destroyed in between "timeupdate" events being fired, since they occur every 250ms, and rAF
objects are destroyed every 166ms (or 10/60hz). Update this constant to destroy the
underlying objects every 333ms (or 20/60hz) so that this common pattern doesn't lead to
excessive rAF platform object turnover.

* platform/Logging.h:
* platform/graphics/DisplayRefreshMonitor.h:
(WebCore::DisplayRefreshMonitor::shouldBeTerminated const):
* platform/graphics/DisplayRefreshMonitor.cpp:
(WebCore::DisplayRefreshMonitor::displayDidRefresh):
* platform/graphics/DisplayRefreshMonitorManager.cpp:
(WebCore::DisplayRefreshMonitorManager::createMonitorForClient):
(WebCore::DisplayRefreshMonitorManager::displayDidRefresh):


Canonical link: https://commits.webkit.org/197313@main
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@226664 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/WebCore/ChangeLog

@@ -1,3 +1,26 @@
+2018-01-09  Jer Noble  <jer.noble@apple.com>
+
+        Many CVDisplayLink threads created and destroyed while watching a YouTube video
+        https://bugs.webkit.org/show_bug.cgi?id=181396
+
+        Reviewed by Simon Fraser.
+
+        When watching some YouTube videos (or any video with default controls), event handlers for
+        the "timeupdate" event which use rAF will cause the underlying platform objects to be
+        destroyed in between "timeupdate" events being fired, since they occur every 250ms, and rAF
+        objects are destroyed every 166ms (or 10/60hz). Update this constant to destroy the
+        underlying objects every 333ms (or 20/60hz) so that this common pattern doesn't lead to
+        excessive rAF platform object turnover.
+
+        * platform/Logging.h:
+        * platform/graphics/DisplayRefreshMonitor.h:
+        (WebCore::DisplayRefreshMonitor::shouldBeTerminated const):
+        * platform/graphics/DisplayRefreshMonitor.cpp:
+        (WebCore::DisplayRefreshMonitor::displayDidRefresh):
+        * platform/graphics/DisplayRefreshMonitorManager.cpp:
+        (WebCore::DisplayRefreshMonitorManager::createMonitorForClient):
+        (WebCore::DisplayRefreshMonitorManager::displayDidRefresh):
+
 2018-01-09  Zalan Bujtas  <zalan@apple.com>
 
         [RenderTreeBuilder] Move RenderElement addChild mutation logic to RenderTreeBuilder

Source/WebCore/platform/Logging.h

@@ -78,6 +78,7 @@ namespace WebCore {
     M(PopupBlocking) \
     M(Progress) \
     M(RemoteInspector) \
+    M(RequestAnimationFrame) \
     M(ResourceLoading) \
     M(ResourceLoadObserver) \
     M(ResourceLoadStatistics) \

Source/WebCore/platform/graphics/DisplayRefreshMonitor.cpp

@@ -85,6 +85,7 @@ void DisplayRefreshMonitor::displayDidRefresh()
 {
     {
         LockHolder lock(m_mutex);
+        LOG(RequestAnimationFrame, "DisplayRefreshMonitor::displayDidRefresh(%p) - m_scheduled(%d), m_unscheduledFireCount(%d)", this, m_scheduled, m_unscheduledFireCount);
         if (!m_scheduled)
             ++m_unscheduledFireCount;
         else

Source/WebCore/platform/graphics/DisplayRefreshMonitor.h

@@ -56,7 +56,7 @@ class DisplayRefreshMonitor : public RefCounted<DisplayRefreshMonitor> {
 
     bool shouldBeTerminated() const
     {
-        const int maxInactiveFireCount = 10;
+        const int maxInactiveFireCount = 20;
         return !m_scheduled && m_unscheduledFireCount > maxInactiveFireCount;
     }
 

Source/WebCore/platform/graphics/DisplayRefreshMonitorManager.cpp

@@ -30,6 +30,7 @@
 
 #include "DisplayRefreshMonitor.h"
 #include "DisplayRefreshMonitorClient.h"
+#include "Logging.h"
 #include <wtf/CurrentTime.h>
 
 namespace WebCore {
@@ -56,6 +57,7 @@ DisplayRefreshMonitor* DisplayRefreshMonitorManager::createMonitorForClient(Disp
     if (!monitor)
         return nullptr;
 
+    LOG(RequestAnimationFrame, "DisplayRefreshMonitorManager::createMonitorForClient() - created monitor %p", monitor.get());
     monitor->addClient(client);
     DisplayRefreshMonitor* result = monitor.get();
     m_monitors.append(WTFMove(monitor));
@@ -105,6 +107,7 @@ void DisplayRefreshMonitorManager::displayDidRefresh(DisplayRefreshMonitor& moni
 {
     if (!monitor.shouldBeTerminated())
         return;
+    LOG(RequestAnimationFrame, "DisplayRefreshMonitorManager::displayDidRefresh() - destroying monitor %p", &monitor);
 
     size_t monitorIndex = m_monitors.find(&monitor);
     if (monitorIndex != notFound)